Amount of memory is enough if you are running 32bit version of windows 7, not enough really for 64bit version and you should be running two identical sticks of memory sold as a matched pair to take full advantage of dual channel mode. If you are purchasing memory, get a matched set 4GB (2x2GB set) for 32bit and 8GB (2x4GB set) for 64bit Windows 7.

Would that be version F8 (board revision 1.x) or version FJ (board revisions 2.x & 2.3)?

"Reset the CMOS"

Did you do it correctly? Did you unplug the power cord 1st? From the manual:

CLR_CMOS (Clearing CMOS Jumper)Use this jumper to clear the CMOS values (e.g. date information and BIOS configurations) and reset the CMOS values to factory defaults. To clear the CMOS values, place a jumper cap on the two pins to temporarily short the two pins or use a metal object like a screwdriver to touch the two pins for a few seconds.

• Always turn off your computer and unplug the power cord from the power outlet before clearing the CMOS values.• After clearing the CMOS values and before turning on your computer, be sure to remove the jumper cap from the jumper. Failure to do so may cause damage to the motherboard.

Did you ever attempt to overclock the Pentium? If not, why not? It is an extremely good overclocker & your board supports 1600MHz FSB so it would have been a perfect setup. 4GHz+ is not out of the question, even with stock cooling.

In order to enter BIOS settings, I have to put the old pentium processor first.So, from there, i set the fsb to 333(for 1333Mhz, the correct fsb of q8400).

Still, the same thing happens. No matter what I did.

Overclocking Pentium? wow!!The reason I wanna change the processor in the first place is because when I play any game(Crysis 2 for example), the CPU went to 100%, then it starts to minimize every 5 secs. Its so annoying, and even FIFA 14 stutters a lot like 100%.

Is it safe to overclock? people say that I have to be careful as the CPU might get fried.

I'm not really a friend of overclocking CPUs.At the end, you pay less life time of the CPU, for the +speed you get.What do you think?Why would Intel, AMD and so forth sell CPUs with more speed, if it's unnecessary, cause everyone can overclock the CPU, to get the same speed for lower cost?

If you want to drive a Ferrari, you can't by a Nissan and tune it up, to get a Ferrari.At the end, you neither have a Ferrari nor a Nissan.

Your analogy of the Ferrari vs Nissan doesn't fly because a Nissan isn't a de-tuned Ferrari. However, most lower end CPUs in a series/family (based on the same CPU core) are just that - detuned versions of their high end cousins. The only difference is the default multiplier assigned to them.

Using the OP's Pentium E5400 as an example, it's based on the Wolfdale-3M core. From wikipedia: the Wolfdale-3M "is used in the Core 2 E7xxx series as well as the E5xxx/E6xxx Pentium Dual-Core and E3xxx Celeron processors". In other words, there are numerous CPUs that use the exact same core. In the Pentium-Wolfdale-E5xxx line, the only difference between the low end E5200 (2.5GHz) & the high end E5800 (3.2GHz) is the multiplier, otherwise they're identical. So in reality, overclocking a E5200 to 3.2GHz does not stress the CPU one bit.

"Why would Intel, AMD and so forth sell CPUs with more speed, if it's unnecessary, cause everyone can overclock the CPU"

Fortunately for AMD & Intel, most people think like you do - "overclocking is bad". Yes, everyone can overclock (provided they have a motherboard that allows it), but the majority don't because they're scared they may break something.

@ stzahms,

Are you using a USB or PS/2 keyboard? If it's USB, try switching to a PS/2. Install the Q8400, then clear CMOS. Boot the system & see if the PS/2 keyboard will allow you to access the BIOS & make the necessary changes.

I started overclocking on a P4 which ran for quite a few years and was retired due to needing even faster. I am now running two machines (one personal, one family) with C2D E7500 & E8200 and both have been overclocked for many years and on Windows 7. As long as it is done intelligently and with reasonable care, it is a viable alternative. I really want to upgrade to a new i5-4670K but my E7500 OC'd still meets my personal computing needs so I am finding it difficult justifying the expense right now.Certainly try getting the Q8400 to work, it should. riider's above suggestions as well as verifying the BIOS version you upgraded to is correct, should be all you need to do as long as the CPU you purchased is a good one (from a reliable source, tested and guarantied).

The only place you need to check to see if the CPU is supported is the motherboard manufacturer's website. I asked you which BIOS version you have but you didn't respond. There are several versions of the GA-G31M-ES2C & they ALL support the Q8400 provided the proper BIOS is installed.

As I stated in response #3, if you have motherboard revision 1.x, you should be running BIOS version F8. If you have board revisions 2.x or 2.3, you should be running BIOS version FJ. The charts below show versions F7 & FC, but if you need to upgrade the BIOS anyways, you should go for the newest available.

Are you sure the new CPU is good? Did you buy it from a reputable vendor or did you get it thru eBay or Craigslist? Personally, I wouldn't even have considered a CPU upgrade. As I explained, you already have a great board/CPU combo, all you need to do is take advantage of it.

E8400 and E7500 are both very good overclockers, the E7500 probably a little bit better.The Q8400 should work so if all else is right, see about getting an exchange on the one you purchased or credit towards one of the above.With any of the above, make sure your RAM is 800MHz DDR2 and you are running everything at a base frequency of 400MHz (FSB1600MHz, DDR2-800MHz (memory multiplier 2.0) , CPU multiplier probably between 7.5 & 9) and do not forget to lock your PCIe at 100MHz.Understand that new i-5 or i-7 4th generation will still blow it away so if you are going to spend more than a little bit of money, consider a complete new build with a modern CPU and appropriate hardware.

Amount of memory is enough if you are running 32bit version of windows 7, not enough really for 64bit version and you should be running two identical sticks of memory sold as a matched pair to take full advantage of dual channel mode. If you are purchasing memory, get a matched set 4GB (2x2GB set) for 32bit and 8GB (2x4GB set) for 64bit Windows 7.

The wattage SHOULD be plenty, considering the GTX650 is not that high a draw card. To be more sure of things, look into your BIOS and report the individual voltages that are listed, your 3.3V, 5V, & 12V numbers should be within +-5% of their nominal values. If you list the individual amperage numbers from the power supply's label (3.3V, 5V, & all 12V #'s) so we can determine exactly how cheap the power supply really is. If this is yours:http://leapfroglobal.com/powerlogic...then the two 10Amp 12Volt rails proves that it is really a cheaply made power supply. At best 20A x 12V = 240Watts, considering that nothing draws much from the other rails (current wise), it really should be considered maybe a 275Watt model. If it is really able to deliver what they say, it should just make it as long as you do not upgrade the graphics. Considering that it is likely that it does not live up to the numbers actually published, means that it is very possible that it might be your cause here. If your voltages are out of range (greater than 5% above or below the listed voltages (11.4V to 12.6V on either of the 12V rails, etc.)), then definitely replace it ASAP.

and btw, I did look up on stucked BIOS on other MOBO. and it happens a lot on gigabyte mobo. some of them tested by changing other parts(ram graphics etc). and some of them managed to get it right. and other unlucky ones did change their mobo.

I have built a few systems with G41 & P43 Gigabyte motherboards for the home and a couple of slightly later ones (early i-3's) for father-in-law's business and have had no problems with any of them so my experience with Gigabyte motherboards is good one.Good luck and keep us up to date on how it goes.

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